protected override void OnElementChanged(ElementChangedEventArgs <DropDownMenuView> e)
{
base.OnElementChanged(e);
if (e.NewElement != null)
{
_dropDownView = (DropDownMenuView)e.NewElement;
if (Control == null)
{
Android.Widget.RelativeLayout wraper = new Android.Widget.RelativeLayout(Android.App.Application.Context);
ContextThemeWrapper theme = new ContextThemeWrapper(Android.App.Application.Context, Mobile.Droid.Resource.Style.Base_Widget_AppCompat_TextView_SpinnerItem);
_nativeView = new Spinner(theme);
_nativeView.OnItemSelectedListener = this;
if (Android.OS.Build.VERSION.SdkInt < Android.OS.BuildVersionCodes.M)
{
_nativeView.SetBackgroundResource(Mobile.Droid.Resource.Drawable.abc_btn_borderless_material);
}
else
{
wraper.SetBackgroundResource(Mobile.Droid.Resource.Drawable.abc_btn_borderless_material);
}
_nativeView.LayoutParameters = new Android.Widget.RelativeLayout.LayoutParams(LayoutParams.MatchParent, LayoutParams.MatchParent);
_dropDownView.SetItemSelection = (i) =>
{
_nativeView.SetSelection(i);
};
ImageView downIcon = new ImageView(Android.App.Application.Context);
var param = new Android.Widget.RelativeLayout.LayoutParams(20, 20);
param.AddRule(LayoutRules.AlignParentRight);
param.AddRule(LayoutRules.CenterInParent);
param.SetMargins(0, 0, 14, 0);
downIcon.LayoutParameters = param;
downIcon.SetImageResource(Mobile.Droid.Resource.Drawable.abc_ic_arrow_drop_right_black_24dp);
wraper.AddView(_nativeView);
wraper.AddView(downIcon);
SetNativeControl(wraper);
}
if (_dropDownView.ItemsSource != null)
{
SetApdater();
}
}
}
